The point of this image is to fool not so internet savvy folk (like say your mom or grandmother) into thinking that people who post reddit "rage face" comics are pedophiles. That's the joke.
Children today often have mobile phones but so too do paedophiles using text message slang. And because they're on edge they dial wrong numbers so watch out for these....
P2PBSH: Pipe to pipe bushman - code for two paedophiles having sex with each other while watching children from a shrub.
DBL: DBL means dusty blonde lulu and that's a male paedophile disguised as a lion.
BALTIMORA: Baltimora - this means literally : "I'm running at them now with my trousers down"...